最後の氷河期における南極の表面温度と高さ
Christo Buizert1, T J Fudge2, William H G Roberts3
1College of Earth Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA. christo.buizert@oregonstate.edu.
Science (New York, N.Y.)
|June 4, 2021
まとめ
この研究は,南極における最後の氷河期最大冷却を明らかにし,西南極は10°C,東南極は4-7°Cに冷却した. これらの発見は,古気候データと気候モデルを調和させています.
科学分野:
- 古代気候学
- 氷河学
- 南極 研究
背景:
- 極地の氷の核に含まれる水に安定したイソトープは 温度を決定する重要な指標です
- これらの代理の校正は,特に東南極では困難です.
- 過去の南極の気候を理解することは 将来の気候変動を予測するのに 極めて重要です
研究 の 目的:
- 南極の表面冷却の大きさと空間的なパターンを再構築する.
- 氷の核のデータと 気候モデルの出力を比較する
- 異なる古気候のプロキシ再構築の間の不一致を調和させるため
主な方法:
- 南極の7つの氷の核から採取した 掘削孔の温度測定と 氷の性質の分析
- トポグラフィの変化を考慮するために,氷の核の空気含有量データを組み込む.
- 再構築された温度を水同位体プロキシデータと気候モデルシミュレーションと比較する.
主要な成果:
- 西南極地域では 工業化以前の時期と比較して 表面が約10°C冷却された.
- 東南極の場所は,約4°Cから7°Cの冷却範囲を示しました.
- 東南極で再構築された冷却は地形的な変化を考慮すると気候モデルと一致しますが,現代のグラデーションに対して校正された水同位体プロキシからの推定値より低いです.
結論:
- この研究は,南極大陸の最後の氷河期最大冷却の精巧な見積もりを提供します.
- 氷河期における 変化した南極の温度反転は,新しい発見と水同位体の観測を調和させるのに役立ちます.
- この研究は南極の古気候再構築の信頼性を高めています
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